Yes. I am arguing from the premise that all cultures have a right to self-determination and that aggression, conquest, and enslavement are immoral.

This may not be the case.

You be sure to tell that to the victims of the Third Reich.

Morality is a matter of perspective.

In many areas, yes. In the area of the right of cultures to self-determination? No. That is a natural right, and it is universal.

From the Borg perspective, their actions have positive moral value.

No they don't. The Borg simply do not care about morality one way or the other. The Borg Collective is sociopathic.

It is unfortunate that their values are incompatible with ours, but this does not make them evil any more than being individuals makes us evil.

I don't consider the fact that they lack individuality to be the thing that makes them evil. The Bynars aren't what we would call individuals, but they're not in any sense evil. I consider the fact that they invade and enslave others to their way of life to be the thing that makes them evil.

And, yes, enslaving foreign cultures is immoral. Period. That's a matter of fact, not of debate.

Because Star Trek has only needed the evolution of lifeforms to tell a story twice. And both times, it turns out that evolution in the Trekverse is a bit different than it is in real life -- the ancient Progenitors seeding humanoid life in "The Chase," and Humans evolving into salamanders in "Threshold."

"Threshold" was not the least bit Realistic. Evolution does not have a set "path" that one can fast-forward an organism towards, as "Threshold" implies. Evolution is simply the emergence of species-wide traits that developed randomly and then spread to subsequent generations then they turn out to have been beneficial to survival and reproduction.